INFO: task syz.1.1975:15638 blocked for more than 143 seconds.
Tainted: G U syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1975 state:D stack:26264 pid:15638 tgid:15638 ppid:5880 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
tty_release_struct+0xad/0xe0 drivers/tty/tty_io.c:1691
tty_release+0xe2d/0x1430 drivers/tty/tty_io.c:1852
__fput+0x3ff/0xb70 fs/file_table.c:468
task_work_run+0x14d/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d6618ebe9
RSP: 002b:00007ffcc2a48528 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f2d663c7da0 RCX: 00007f2d6618ebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f2d663c7da0 R08: 000000000004d134 R09: 0000001ec2a4881f
R10: 00007f2d663c7cb0 R11: 0000000000000246 R12: 0000000000084039
R13: 00007f2d663c5fa0 R14: ffffffffffffffff R15: 00007ffcc2a48640
INFO: task syz.3.1977:15655 blocked for more than 143 seconds.
Tainted: G U syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1977 state:D stack:25512 pid:15655 tgid:15645 ppid:5871 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
chrdev_open+0x231/0x6a0 fs/char_dev.c:414
do_dentry_open+0x97f/0x1530 fs/open.c:965
vfs_open+0x82/0x3f0 fs/open.c:1095
do_open fs/namei.c:3887 [inline]
path_openat+0x1de4/0x2cb0 fs/namei.c:4046
do_filp_open+0x20b/0x470 fs/namei.c:4073
do_sys_openat2+0x11b/0x1d0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x174/0x210 fs/open.c:1461
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f909238ebe9
RSP: 002b:00007f9093284038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f90925c6180 RCX: 00007f909238ebe9
RDX: 0000000000101e81 RSI: 0000200000000400 RDI: ffffffffffffff9c
RBP: 00007f9092411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f90925c6218 R14: 00007f90925c6180 R15: 00007ffc2690f498
INFO: task syz.3.1977:15656 blocked for more than 143 seconds.
Tainted: G U syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1977 state:D stack:28856 pid:15656 tgid:15645 ppid:5871 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760
tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
chrdev_open+0x231/0x6a0 fs/char_dev.c:414
do_dentry_open+0x97f/0x1530 fs/open.c:965
vfs_open+0x82/0x3f0 fs/open.c:1095
do_open fs/namei.c:3887 [inline]
path_openat+0x1de4/0x2cb0 fs/namei.c:4046
do_filp_open+0x20b/0x470 fs/namei.c:4073
do_sys_openat2+0x11b/0x1d0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_openat fs/open.c:1466 [inline]
__se_sys_openat fs/open.c:1461 [inline]
__x64_sys_openat+0x174/0x210 fs/open.c:1461
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f909238ebe9
RSP: 002b:00007f9093263038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f90925c6270 RCX: 00007f909238ebe9
RDX: 0000000000000102 RSI: 0000200000000980 RDI: ffffffffffffff9c
RBP: 00007f9092411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f90925c6308 R14: 00007f90925c6270 R15: 00007ffc2690f498
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c10e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/11304:
#0: ffff88814e22f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fc52f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
2 locks held by kworker/u10:11/15311:
#0: ffff888146293948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000410fd10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u10:15/15315:
#0: ffff888146293948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc9000b3f7d10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u10:16/15316:
#0: ffff888146293948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900044bfd10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u10:17/15317:
#0: ffff888146293948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211
#1: ffffc900040bfd10 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212
2 locks held by kworker/u10:18/15318:
2 locks held by syz.0.1937/15450:
#0: ffffffff9042acd0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e9d97c8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b10 fs/nfsd/nfsctl.c:1919
1 lock held by syz.1.1975/15638:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_release_struct+0xad/0xe0 drivers/tty/tty_io.c:1691
4 locks held by syz.2.1976/15649:
1 lock held by syz.3.1977/15655:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.3.1977/15656:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.4.1993/15764:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.7.1994/15833:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.6.1987/15826:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.6.1987/15828:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.5.1996/15849:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.8.2004/15932:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.0.2010/16010:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.9.2009/16009:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.1.2016/16051:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.2.2017/16074:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.3.2018/16140:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.4.2042/16300:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.4.2042/16303:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.6.2044/16309:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: ptmx_open drivers/tty/pty.c:823 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0xff/0x360 drivers/tty/pty.c:790
1 lock held by syz.6.2044/16311:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.5.2049/16492:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.7.2051/16541:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.8.2052/16564:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: ptmx_open drivers/tty/pty.c:823 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: ptmx_open+0xff/0x360 drivers/tty/pty.c:790
1 lock held by syz.8.2052/16565:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.9.2053/16571:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
1 lock held by syz.9.2053/16572:
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8f2cbbc8 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x53e/0xf90 drivers/tty/tty_io.c:2120
2 locks held by syz-executor/16600:
#0: ffffffff8f6e3180 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#0: ffffffff8f6e3180 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#0: ffffffff8f6e3180 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:574
#1: ffffffff90387808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff90387808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff90387808 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x600/0x2000 net/core/rtnetlink.c:4056
2 locks held by syz-executor/16619:
1 lock held by syz-executor/16621:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U syzkaller #0 PREEMPT(full)
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf0e/0x1260 kernel/hung_task.c:491
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245